MOTHERS-TO-BE, STAY CALM... YOUR CHILD’S FUTURE DEPENDS ON IT
Researchers have discovered how the link between the levels of stress hormones a foetus
is exposed to in the womb and the development of mood disorders like anxiety and depression in later life, might be controlled in the body. We’ve known for some time that a foetus’ experiences in the womb can have long-lasting effects on physical and mental health. This so-called ‘foetal programming’ is partly due to naturally produced stress hormones in the mother (called glucocorticoids). The most important stress hormone is cortisol, which can stunt growth, alter the timing of tissue growth, and have various other long-lasting effects. Stress or emotional trauma in an expectant mother increases her cortisol levels, potentially harming the developing baby. Professor Megan Holmes revealed at the conference
that, together with colleagues at the University of Edinburgh, she has discovered a way the foetal brain protects itself against stress hormones before they can cause harm. They have found an enzyme in the placenta and in foetal brains (called 11β-HSD2) that appears to act as a protective barrier. By breeding mice lacking 11β-HSD2, Holmes saw that foetuses exposed to high levels of stress hormones were particularly vulnerable to reduced growth and (mouse) mood disorders. Without this enzyme, the mother’s placenta was smaller and didn’t transport nutrients efficiently. Professor Holmes thinks this finding may offer clues for developing medications to protect foetuses from the effects of maternal stress. She hopes she may even be able to uncover drugs that could reverse these mood disorder effects. Her research continues.